题目内容
（选用介词 of 或 for 完成句子） It's kind __________ Lucy to give the seat to the old lady on a bus．
（选用介词 of 或 for 完成句子） It's bad __________ your teeth to eat too much sweet．
（选用介词 of 或 for 完成句子） It's generous __________ your mother to give as so much delicious food．
（选用介词 of 或 for 完成句子） It's impolite __________ us to talk in the library．We should keep quiet．
（选用介词 of 或 for 完成句子） It's interesting __________ children to go swimming in the river in summer．
